1. Field of the Invention
The present general inventive concept relates to an image forming apparatus, and more particularly to a multi-pass type image forming apparatus.
2. Description of the Related Art
An image forming apparatus is an apparatus that prints an image on a printing medium, e.g., paper, according to an input image signal. One type of the above-mentioned image forming apparatus, is an electrophotographic color image forming apparatus which is configured such that a laser beam is scanned across a photosensitive body that is charged with a predetermined electric potential to form an electrostatic latent image on the outer peripheral surface of the photosensitive body. The electrostatic latent image is developed into a visible image by supplying a developer (i.e., toner, or toner and carrier) to the electrostatic latent image, and the visible image is then transferred onto and fixed to paper.
Typically, toners of four colors of yellow Y, magenta M, cyan C, and black B are used in the color image forming apparatus, and accordingly four developing devices are needed to adhere the toners of four colors to the electrostatic latent image.
There are two types of image forming apparatuses used when forming a color image. One type of image forming apparatus is a single-pass type in which four developing devices are respectively provided with four photosensitive bodies. The other type of image forming apparatus is a multi-pass type in which four developing devices hold one photosensitive body in common.
One example of the conventional multi-pass type image forming apparatus is disclosed in Korean Patent Registration No. 10-633097. The conventional multi-pass type color image forming apparatus is configured such that the exposure, development and transfer of the respective colors associated with each color toner are repeated on one photosensitive body to overlappingly form a color image on an intermediate transfer medium, and the color image is transferred onto and fixed to paper.
However, the above conventional multi-pass type color image forming apparatus has a problem such that the photosensitive body needs to have a diameter large enough to accommodate all four developing devices to be positioned near the photosensitive body at one time, thereby, placing limitations when manufacturing the image forming apparatus compactly.